Vernier gears are jus adjustable can gears. Because the ba on motor hd duel vct the au
ecu won't control them so the cam timing will not be correct. After adding boost it will need to be tuned but someone correct me of I'm wron but I don't think the s1 au had a boost cut 2 or 3 psi. Not to sure about how other guys went about this. As for the motor when boosted I haven't done anything to it, I jus wanted to see if I could get the ba motor running good before I spent any more money on it. If all goes well with it then I blow it up then I will spend the money to get a turbo motor. I jus didn't want to buy a ba turbo motor then find out I couldn't get it to run properly. Will keep you posted after the tune